The present invention relates to a new and distinct variety of citrus rootstock named ‘UFR-4’. The Plant Improvement Team in Lake Alfred, Fla. has pioneered the development and testing of allotetraploid citrus rootstocks. ‘UFR-4’ is an allotetraploid zygotic hybrid derived from a conventional cross of two somatic hybrids previously produced by protoplast fusion. The somatic hybrid seed parent is ‘Nova’ mandarin hybrid+‘Hirado Buntan’ pummelo (zygotic seedling), and the somatic hybrid pollen parent is ‘Cleopatra’ mandarin+‘Argentine’ trifoliate orange.